European Journal of Radiology

Editorial Board

2010-08-01

European Journal of Radiology - Appreciation to Reviewers 2009

2010-08-01

Whole-brain voxel-based morphometry of white matter in mild cognitive impairment

Zhiqun Wang, Xiaojuan Guo, Zhigang Qi, Li Yao, Kuncheng Li — 2010-08-01

Abstract: Purpose: The purpose of this study was to analyze whole-brain white matter changes in mild cognitive impairment (MCI).Materials and methods: We studied 14 patients with MCI and 14 age- and sex-matched healthy control subjects using voxel-based morphometry (VBM) on T1-weighted 3D datasets. The data were collected on a 3T MR system and analyzed by SPM2 to generate white matter volume maps.Results: Voxel-based morphometry revealed diffusively reduced white matter in MCI prominently including the bilateral temporal gyrus, the right anterior cingulate, the bilateral superior and medial frontal gyrus and right parietal angular gyrus. White matter reduction was more prominent in anterior regions than that in posterior regions.Conclusion: Whole-brain white matter reduction in MCI patients detected with VBM has special distribution which is in line with the white matter pathology of MCI.

Regional diffusion changes of cerebral grey matter during normal aging—A fluid-inversion prepared diffusion imaging study

2010-08-01

Abstract: Background and purpose: Although diffusion characteristics of white matter (WM) and its aging effects have been well described in the literature, diffusion characteristics of grey matter (GM), especially the cortical GM, have not been fully evaluated. In the present study, we used the fluid-inversion prepared diffusion imaging (FLIPD) technique to determine if there are age-related water diffusivity changes in GM.Materials and methods: 120 healthy volunteers were recruited for our study. They were divided into three age groups: group one (20–39 years old), group two (40–59 years old) and group three (60 years or older). All patients were evaluated with MRI using FLIPD at 3.0T. Apparent diffusion coefficient (ADC) values of the frontal GM, cingulate cortex and thalami were determined bilaterally by region-of-interest analysis.Results: Group three had significantly higher ADC values in both thalami and the left frontal GM compared to group two or group one. No ADC value difference was found among the three groups in the right frontal GM and bilateral cingulate cortex. There was a significant positive correlation between individual ADC values and age in both thalami and left frontal GM. For the cingulate cortex and the right frontal GM, ADC values did not correlate significantly with advancing age.Conclusion: Statistically significant age-related diffusion changes were observed in both thalami and the left frontal cortex. The data reported here may serve as a reference for future studies.

Recovery of opthalmoplegia associated with cavernous sinus dural arteriovenous fistulas after transvenous cavernous sinus packing

Xianli Lv, Chuhan Jiang, Youxiang Li, Xinjian Yang, Zhongxue Wu — 2010-08-01

Abstract: Background: We report the recovery of ophthalmoplegia in 11 patients with cavernous sinus dural arteriovenous fistula (CSDAVF) after sinus packing at follow-up.Methods: Of 18 patients with CSDAVF treated with transvenous cavernous sinus packing between August 2002 and December 2007 at Beijing Tiantan Hospital, there were 9 patients with initial CNIII or CNVI dysfunction and 2 patients with CNVI dysfunction immediately after cavernous sinus packing selected and reevaluated.Results: Of 11 patients with CNIII or CNVI palsy, recovery was complete in 10. In 1 patient, complete CNVI palsy was unchanged because the CSDAVF was not cured. There were 6 men and 5 women with a mean age of 52.9 years. In 5 patients, CNVI palsy was associated with chemosis, proptosis and pulsatile tinnitus. Timing of treatment after onset of symptoms was from 4 to 35 days in 9 patients. All CSDAVFs were Barrow type D. Mean follow-up after treatment was 17.7 months (range, 2–54 months).Conclusion: CSDAVF-induced CNIII or CNVI palsies can be cured after cavernous sinus packing transvenously in most patients.

Dual-time point scanning of integrated FDG PET/CT for the evaluation of mediastinal and hilar lymph nodes in non-small cell lung cancer diagnosed as operable by contrast-enhanced CT

2010-08-01

Abstract: Purpose: To evaluate whether dual-time point scanning with integrated fluorine-18 fluorodeoxyglucose (18F-FDG) positron emission tomography and computed tomography (PET/CT) is useful for evaluation of mediastinal and hilar lymph nodes in non-small cell lung cancer diagnosed as operable by contrast-enhanced CT.Materials and methods: PET/CT data and pathological findings of 560 nodal stations in 129 patients with pathologically proven non-small cell lung cancer diagnosed as operable by contrast-enhanced CT were reviewed retrospectively. Standardized uptake values (SUVs) on early scans (SUVe) 1h, and on delayed scans (SUVd) 2h after FDG injection of each nodal station were measured. Retention index (RI) (%) was calculated by subtracting SUVe from SUVd and dividing by SUVe. Logistic regression analysis was performed with seven kinds of models, consisting of (1) SUVe, (2) SUVd, (3) RI, (4) SUVe and SUVd, (5) SUVe and RI, (6) SUVd and RI, and (7) SUVe, SUVd and RI. The seven derived models were compared by receiver-operating characteristic (ROC) analysis. k-Fold cross-validation was performed with k values of 5 and 10. p<0.05 was considered statistically significant.Results: Model (1) including the term of SUVe showed the largest area under the ROC curve among the seven models. The cut-off probability of metastasis of 3.5% with SUVe of 2.5 revealed a sensitivity of 78% and a specificity of 81% on ROC analysis, and approximately 60% and 80% on k-fold cross-validation.Conclusion: Single scanning of PET/CT is sufficiently useful for evaluating mediastinal and hilar nodes for metastasis.

Empirical description of bronchial and nonbronchial arteries with MDCT

Hong Yu, Shi-Yuan Liu, Hui-Min Li, Xiang-Sheng Xiao, Wei-Hua Dong — 2010-08-01

Abstract: Purpose: We aimed to retrospectively evaluate bronchial and nonbronchial systemic arteries using multi-detector row helical computed tomographic (MDCT) angiography in patients with pulmonary disorders.Materials and Methods: Thirty-nine patients (24 men, 15 women; mean age, 63.4 years; range, 20–82 years) with congenital and acquired pulmonary disorders of the bronchial and nonbronchial systemic arteries underwent multi-detector row helical computed tomographic angiography of the thorax using a 16-detector row scanner. Each of these patients had experienced an episode of hemoptysis. Computed tomographic angiogram data, which included maximum intensity projections, multiplanar reconstruction, and three-dimensional volume-rendered images, were used to retrospectively analyse the characteristics of the bronchial and nonbronchial systemic arteries.Results: We identified a total of 128 bronchial arteries (76 on the right side and 52 on the left) in 39 patients. We detected 42 nonbronchial systemic artery branches, including 19 internal mammary artery branches, 8 subclavian artery branches, 8 inferior phrenic artery branches, 5 intercostal artery branches, 1 thyrocervical trunk branch, and 1 celiac trunk branch. Thirty-five dilated and tortuous nonbronchial systemic arteries entered into the lung parenchyma and extended down to the lesions. Every case, except the one case of sequestration, was associated with pleural thickening where the vascular structures passed through the extrapleural fat.Conclusions: The variations in both the bronchial artery anatomy and the location and type of the nonbronchial arteries were great. Nonbronchial arteries may be a significant source of hemoptysis. MDCT angiography can be used to detect detailed anatomical information about the origins and courses of bronchial and nonbronchial systemic arteries and their pathophysiologic features.

Hybrid cardiac SPECT/64-slice CTA-derived LV function parameters: Correlation and reproducibility assessment

2010-08-01

Abstract: The purpose of this study is to define the relationship between SPECT and CTA measured parameters of left ventricular (LV) function and volumes obtained in a single session using SPECT/64-slice CT hybrid imaging device, and in addition, to assess the reproducibility of LV parameters measured using 64-slice CTA.Materials and methods: Seventy-six patients with suspected or known coronary artery disease underwent cardiac CTA and GSPECT in one session using a hybrid SPECT/CT device.LV end-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (EF) were measured on each component of the hybrid device. For the CTA component, these parameters were re-measured by the same investigator and by a second investigator with an interval of 3–54 weeks. Corresponding GSPECT and CTA measured parameters were compared. For CTA, intra-observer and inter-observer variability of LV function and volume measurements were calculated.Results: A very good correlation was found between the GSPECT and CTA measured LVEF (r=0.81), ESV (r=0.90) and EDV (r=0.82). There was a small positive difference by CTA measured LVEF (3.9±14.2%), and more prominent positive differences by CTA measured ESV and EDV (9.8±14.8 and 44.9±23.1cm3, respectively). There was excellent reproducibility in the measurements of all parameters with very low intra- and inter-observer variability (r=0.93 for EF and 0.98 for EDV and ESV).Conclusions: Although a good correlation was found between the EF measurements obtained from CTA and SPECT, interchangeable use of EF measurements between the two modalities should be done cautiously and interchangeable use of LV EDV and ESV should be avoided.

What is the best contrast injection protocol for 64-row multi-detector cardiac computed tomography?

Jin-guo Lu, Bin Lv, Xiong-biao Chen, Xiang Tang, Shi-liang Jiang, Ru-ping Dai — 2010-08-01

Abstract: Objective: To determine the optimal contrast injection protocol for 64-MDCT coronary angiography.Materials and methods: One hundred and fifty consecutive patients scheduled to undergo retrospectively electrocardiographically gated 64-MDCT. Each 30 patients were assigned to use a different contrast protocol: group 1: uniphasic protocol (contrast injection without saline flush); group 2: biphasic protocol (contrast injection with saline flush); group 3A, 3B and 3C: triphasic protocol (contrast media+different saline diluted contrast media+saline flush). Image quality scores and artifacts were compared and evaluated on both transaxial and three-dimensional coronary artery images among each contrast protocol.Results: Among the triphasic protocol groups, group 3A (30%:70% contrast media–saline mixture was used in second phase) used the least contrast media and had the least frequency of streak artifacts, but there were no significant differences in coronary artery attenuation, image quality, visualization right and left heart structures. Among the uniphasic protocol group (group 1), biphasic protocol group (group 2) and triphasic protocol subgroup (group 3A), there were no significant differences in image quality scores of coronary artery (P=0.18); uniphasic protocol group had the highest frequency of streak artifacts (20 cases) (P<0.05) and had the most amount contrast media (67.0±5.3ml); biphasic protocol group had the least amount of contrast media (59.9±4.9ml) (P<0.05) and had the highest attenuation of left main coronary artery and right coronary artery (P<0.01), but had the least amount of clear visualization right heart structure (6 cases); triphasic protocol group (group 3A) had the most amount of clear visualization right heart structures (29 cases) were the most among the three groups (P<0.05).Conclusion: Biphasic protocol are superior to the traditional uniphasic protocols for using the least total contrast media, having the least Streak artifacts and without image quality degradation. However, it is also important to visualize the right atrium and ventricle, so triphasic protocol (30%:70% contrast media–saline mixture was used in second phase) should be used for 64-MDCT coronary CT angiography.

Gadofosveset trisodium-enhanced magnetic resonance angiography of the left atrium—A feasibility study

2010-08-01

Abstract: Aim: Imaging of the left atrium is regularly performed prior to pulmonary vein isolation. The aim of the study was to evaluate the feasibility of contrast-enhanced high-resolution magnetic resonance angiography (MRA) of the left atrium using the blood-pool contrast agent gadofosveset trisodium in comparison to noncontrast MRA.Materials and methods: Twenty consecutive patients were examined by free-breathing electrocardiogram-gated whole-heart MRA (reconstructed spatial resolution, 0.7mm×0.6mm×0.8mm) with a noncontrast T2-prepared steady state free precession sequence (T2-prep SSFP) and a gadofosveset trisodium-enhanced inversion-recovery SSFP sequence (CE IR-SSFP). Contrast-to-noise ratio (CNR) of blood in the left atrium was determined. Depiction of the left atrium was rated by two radiologists in consensus. A cardiologist segmented the MR data sets and rated depiction of the left atrium.Results: Five of 20 patients had irregular breathing patterns with navigator efficiency less than 35% and were excluded from evaluation. CNR was significantly higher for CE IR-SSFP compared with T2-prep SSFP (18.4±5.3 vs. 11.7±3.5, p<0.01). Depiction of the left atrium by T2-prep SSFP was rated as good in four patients, moderate in ten patients, and poor in one patient, whereas depiction of the left atrium by CE IR-SSFP was rated as excellent in nine patients, good in four patients, and moderate in two patients. CE IR-SSFP allowed for semiautomated segmentation of the left atrium in 15 patients, whereas T2-prep SSFP allowed for segmentation only in ten patients.Conclusion: Gadofosveset trisodium-enhanced MRA of the left atrium is feasible with significantly improved image quality compared to noncontrast MRA.

Effect of cardiac function on aortic peak time and peak enhancement during coronary CT angiography

2010-08-01

Abstract: Purpose: To examine the manner in which cardiac function affects the magnitude and timing of aortic contrast enhancement during coronary CT angiography (CTA).Materials and methods: Twenty-nine patients (21 men, 8 women; mean age, 64.4±13.4 years; mean weight, 59.4±10.3kg) underwent measurement of cardiac output within 2 weeks of coronary CTA. The cardiac output of each patient was measured by the thermodilution technique and the cardiac index was calculated from the body surface area. During coronary CTA, attenuation of the descending aorta was measured at the workstation every 3s. The aortic peak time (APT) and aortic peak enhancement (APE) of each patient were calculated. Pearson's correlation coefficient analysis was used to investigate the relationships between the cardiac output or cardiac index and APT or APE. Furthermore, the relationship between patient factors or parameters on test bolus injection and APT or APE was also evaluated.Results: The range of cardiac output, cardiac index, APT, and APE was 1.55–10.46L/min (mean: 4.77±2.13), 1.11–5.30L/(min-m2) (mean: 3.28±1.08), 25–51s (mean: 38.3±7.5), and 273.1–598.1HU (mean: 390.4±72.1), respectively. With an increase in the cardiac index, both APT (r=−0.698, p<0.0001) and APE (r=−0.573, p=0.0009) decreased. There were significant correlations between the patient body weight and APT and APE with the test bolus injection, and with APT and APE during coronary CTA.Conclusion: The APT and APE during coronary CTA are closely related to cardiac function.

Unusual malignant tumors of the breast: MRI features and pathologic correlation

2010-08-01

Abstract: Unusual malignant breast tumors are well-differentiated subtypes of invasive ductal carcinoma, including mucinous, tubular, medullary and papillary carcinomas, and account for about 10% of malignant breast tumors. They are increasingly being encountered during magnetic resonance imaging (MRI) examinations of the breast. Therefore, breast radiologists should be aware of their appearance on MRI.This review provides an overview of MRI characteristics of a range of unusual tumors (mucinous carcinoma, medullary carcinoma, tubular carcinoma, intraductal papillary carcinoma, intracystic papillary carcinoma and invasive papillary carcinoma), highlighting specific clues for diagnosis and correlating MRI and pathologic features. Many unusual breast tumors exhibit MRI features similar to those of benign or low suspicious lesions (oval shape, well-defined margins, high signal intensity on T2-weighted images, continuous increase kinetics, i.e. type I dynamic curve), leading to a possible misdiagnosis. Nevertheless, an understanding of pathologic features of these tumors, especially tissue content (mucinous, fibrous) and growth pattern, can help to define some specific clues for their diagnosis.

Diagnosis of portal vein thrombosis discontinued with liver tumors in patients with liver cirrhosis and tumors by contrast-enhanced US: A pilot study

2010-08-01

Abstract: Aims: We assessed the role of contrast-enhanced ultrasound (CEUS) in the differential diagnosis between benign and malignant portal vein thrombosis (PVT) in patients who had liver tumors.Methods: Seventeen consecutive patients who had cirrhosis, liver tumors, and PVT were prospectively studied with CEUS. CEUS was performed at low mechanical index after intravenous administration of a second-generation contrast agent (SonoVue, Bracco, Milan, Italy). Presence or absence of thrombus enhancement on CEUS were considered diagnostic for malignant or benign PVT. Five patients also underwent percutaneous portal vein fine-needle biopsy under US guidance. All patients were followed-up. Shrinkage of the thrombus and/or recanalization of the vessels on CDUS during follow-up were considered definitive evidence of the benign nature of the thrombosis, whereas the enlargement of the thrombus, disruption of the vessel wall, and parenchymal infiltration over follow-up were considered consistent with malignancy.Results: Follow-up showed signs of malignant thrombosis in 14 of 17 patients. CEUS showed early arterial enhancement of the PVT in 14 patients of 14 malignant PVT, 1 patient of 3 benign PVT and the absence of thrombus enhancement in 2 patients of 3 benign PVT. FNB confirmed the results for malignant PVT in four of five patients, for benign granulomatous inflammation PVT in one of five patients in which CEUS showed early arterial enhancement of the PVT. The sensitivity, specificity and accuracy is 100%, 66.7% and 93.3% at diagnosis of malignant PVT using CEUS. In one patient with intrahepatic bile duct stone, CEUS were positive for malignant PVT, whereas FNB was negative (benign granulomatous inflammation PVT); follow-up examination confirmed benign PVT.Conclusion: CEUS seems to be the pretty sensitive and specific test for diagnosing malignant portal vein thrombosis in patients with cirrhosis and tumors.

A computed tomography Iron Index

Hussain Isma’eel, Khaled M. Musallam, Matthew Budoff, Ali T. Taher — 2010-08-01

Magnetic resonance imaging (MRI) of the heart remains to-date the reference standard for non-invasive assessment of cardiac iron-overload in thalassemia major patients . The widespread of this modality is hindered by technical demands, cost, lack of interpretation expertise, and by being cumbersome for the patient (e.g. need for intubation among pediatric patients). Recently, it was demonstrated that Internet-based transfer of acquired images may resolve the local expertise demand. However, the search for other modalities to assess cardiac iron-overload is still highly needed; especially with the relative inadequacy of the currently available blood biomarkers that can serve to identify iron-overloaded hearts.

Evaluation of angiogenesis in colorectal carcinoma with multidetector-row CT multislice perfusion imaging

2010-08-01

Abstract: To evaluate the correlation between 64 multidetector-row CT (64MDCT) perfusion imaging in colorectal carcinoma and microvessel density (MVD) and vascular endothelial growth factor (VEGF), 64MDCT perfusion imaging was performed in 33 patients with pathologically verified colorectal carcinoma. These images were analyzed with perfusion functional software, and time–density curves (TDC) were created for the region of interest (ROI) encompassing the tumor, the target artery and vein. The individual perfusion maps generated indicated blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability-surface area product (PS). MVD and VEGF were evaluated by immunohistochemical staining with anti-CD34 and anti-VEGF, respectively. Correlations between MVD or VEGF with CT perfusion parameters and clinicopathological factors (Dukes’ stages, invasion depth, and lymph node and liver metastasis) were also investigated. MVD in the colorectal carcinoma was 22.61±9.01 per ×200 field. The scores obtained for VEGF expression were 4.15±1.09. VEGF staining was positive in 25 of 29 tumors (86.2%). There was no significant correlation between the presence of MVD, VEGF expression and clinicopathological factors (P>0.05). There was also no correlation between MVD, VEGF expression, and any dynamic CT parameters (P>0.05). The BV and MTT were significantly higher in tumors demonstrating serous coat invasion than in those without it (t=−2.63, −2.24, P=0.0137, 0.0331, respectively). BV was also significantly correlated with tumor size (r=0.41, P=0.02). Neither BF nor PS was correlated with clinicopathological factors. In conclusion, 64MDCT perfusion imaging, MVD, and VEGF may reflect angiogenic activity, but no significant correlation among these factors.

Enhancement pattern of hilar cholangiocarcinoma: Contrast-enhanced ultrasound versus contrast-enhanced computed tomography

2010-08-01

Abstract: Objective: To compare the enhancement pattern of hilar cholangiocarcinoma on contrast-enhanced ultrasound (CEUS) with that on contrast-enhanced computed tomography (CECT).Methods: Thirty-two consecutive patients with pathologically proven hilar cholangiocarcinomas were evaluated by both low mechanical index CEUS and CECT. The enhancement feature of the tumor, portal vein infiltration, and lesion conspicuity on them was investigated.Results: In the arterial phase, the numbers of the lesions showing hyperenhancement, isoenhancement, and hypoenhancement, were 14 (43.8%), 14 (43.8%), and 4 (12.6%), on CEUS, and 12 (37.5%), 9 (28.1%), and 11 (34.4%), on CECT (P=0.162). In portal phase, the numbers of the lesions showing hypoenhancement, isoenhancement, and hyperenhancement were 30 (93.8%), 1 (3.1%), and 1 (3.1%), on CEUS, and 23 (71.9%), 8 (25.0%), and 1 (3.1%), on CECT (P=0.046). The detection rates for portal vein infiltration were 84.2% (16/19) for baseline ultrasound, 89.5% (17/19) for CEUS, and 78.9% (15/19) for CECT (all P>0.05 between every two groups). CEUS significantly improved the lesion conspicuity in comparison with CECT. CEUS and CECT made correct diagnoses in 30 (93.8%) and 25 (78.1%) lesions prior to pathological examination (P=0.125).Conclusion: The enhancement pattern of hilar cholangiocarcinoma on CEUS was similar with that on CECT in arterial phase, whereas in portal phase hilar cholangiocarcinoma shows hypoenhancement more likely on CEUS. CEUS and CECT lead to similar results in evaluating portal vein infiltration and diagnosis of this entity.

Hepatic perfusion changes in an experimental model of acute pancreatitis: Evaluation by perfusion CT

2010-08-01

Abstract: Purpose: It is known that acute pancreatitis may cause secondary changes in several organs. Liver is one of these involved organs. In different experimental studies hepatic damages were shown histopathologically in acute pancreatitis but there are a few studies about perfusion disorders that accompany these histopathologic changes. Perfusion CT (pCT) provides the ability to detect regional and global alterations in organ blood flow. The purpose of the study was to describe hepatic perfusion changes in experimental acute pancreatitis model with pCT.Materials and methods: Forty Sprague–Dawley rats of both genders with average weights of 250g were used. Rats were randomized into two groups. Twenty rats were in control group and 20 in acute pancreatitis group. pCT was performed. Perfusion maps were formed by processing the obtained images with perfusion CT software. Blood flow (BF) and blood volume (BV) values were obtained from these maps. All pancreatic and liver tissues were taken off with laparotomy and histopathologic investigation was performed. Student's t test was used for statistical analyses.Results: In pCT we found statistically significant increase in blood volume in both lobes of liver and in blood flow in right lobe of the liver (p<0.01). Although blood flow in left lobe of the liver increased, it did not reach statistical significance.Conclusion: The quantitative analysis of liver parenchyma with pCT showed that acute pancreatitis causes a significant perfusion changes in the hepatic tissue. Systemic mediators seem to be effective as well as local inflammatory changes in perfusion changes.

Normal small bowel wall characteristics on MR enterography

Carmel G. Cronin, Eithne Delappe, Derek G. Lohan, Clare Roche, Joseph M. Murphy — 2010-08-01

Abstract: Purpose: To assess the normal small bowel parameters, namely bowel diameter, bowel wall thickness, number of folds (valvulae connivientes) per 2.5cm (in.), fold thickness and interfold distance per small bowel segment (duodenum, jejunum, proximal ileum, distal ileum and terminal ileum) on MR enterography.Materials and methods: Between September 2003 and January 2008, 280 MR enterography examinations were performed for investigation of known or suspected small bowel pathology. 120 of these examinations were normal. Sixty-five (m=29, f=36, mean age=34 years, range=17–73 years) of 120 examinations without a prior small bowel diagnosis, with no prior or subsequent abnormal radiology or endoscopy examinations, no prior small bowel surgery and with a minimum 3 years follow-up demonstrating normality were retrospectively evaluated for the described small bowel parameters.Results: We found the mean diameter of the duodenum to be 24.8mm (S.D.=4.5mm), jejunum to be 24.5mm (S.D.=4.2mm), proximal ileum to be 19.5mm (S.D.=3.6mm), distal ileum to be 18.9mm (S.D.=4.2mm) and terminal ileum to be 18.7mm (S.D.=3.6mm). The number of folds per 2.5cm varied from 4.6 in the jejunum to 1.5 in the terminal ileum. The fold thickness varied from 2.1mm in the duodenum to 1.8mm in the terminal ileum. The small bowel parameters gradually decreased in size from the duodenum to the smallest measurements which were in the terminal ileum. The bowel wall is similar in size throughout the small bowel measuring 1.5±0.5mm.Conclusion: These results provide the mean, range of normality and standard deviation of the small bowel parameters per segment on the current population on MR enterography. From our experience, knowledge of these parameters is extremely helpful and essential in the everyday assessment of MR enterography studies.

Magnetic resonance imaging in the evaluation of the gastric emptying and antral motion: Feasibility and reproducibility of a fast not invasive technique

2010-08-01

Abstract: Purpose: The aim of this study was to evaluate reproducibility of a fast MRI protocol to measure gastric emptying and motility of the gastric antrum.Methods and materials: Gastric emptying and antral speed were measured in 12 type 1 diabetic patients (mean age 43 years) and 9 healthy volunteers (mean age 31 years). Subjects, fasting from 6h, were evaluated in supine position using a 1.5T MR scanner and a eight-channels phased-array body coil after ingestion of 400ml of a vanillas pudding mixed with 5ml of Gd-DTPA. Axial 3D T1w sequence at 0 and 30min for volume evaluation and cine-steady state acquisition every 5min for a total time of 30min for gastric wave speed assessing were acquired. Two blinded observers extrapolated T½ from gastric volume assessment and speed of gastric waves.Results: All the patients tolerated the examination. The T½ cut-off was of 115min with an accuracy in differentiate controls from diabetics of 96% (95% CI 0.766–0.992; p<0.001), while the antral speed cut-off was of 0.15mm/s with an accuracy of 87% (95% CI 0.628–0.977; p<0.001). The inter-observer agreement for the volumes at time 0 and 30min was respectively 0.983 (95% CI 0.9628–0.9929; p<0.001) and 0.9933 (95% CI 0.9847–0.9971; p<0.001) with an agreement of 0.9918 (95% CI 0.9853–0.9954; p<0.001), while for antral speed it was of 0.935 (95% CI 0.9097–0.9528; p<0.001).Conclusions: MRI is a reproducible technique for the evaluation of gastric emptying and antral motility.

ADC measurements of lymph nodes: Inter- and intra-observer reproducibility study and an overview of the literature

Thomas C. Kwee, Taro Takahara, Peter R. Luijten, Rutger A.J. Nievelstein — 2010-08-01

Abstract: Purpose: Apparent diffusion coefficient (ADC) measurements in diffusion-weighted magnetic resonance imaging (DWI) may be of value in discriminating malignant from non-malignant lymph nodes, provided that they are reproducible. The aim of this study was to determine the inter- and intra-observer reproducibilities of ADC measurements of lymph nodes and to provide an overview of the current literature on ADC measurements in the characterization of lymph nodes.Materials and methods: Twenty healthy volunteers underwent DWI of the head and neck region and the pelvic region, at b-values of 0 and 1000s/mm2. Two observers independently and blindly measured ADCs of lymph nodes. Inter- and intra-observer reproducibilities were assessed using the Bland–Altman method.Results: Mean ADCs of normal lymph nodes (in 10−3mm2/s) varied between 1.15 and 1.18. Ranges of mean ADC difference±limits of agreement (in 10−3mm2/s) for inter-observer agreement were −0.03 to 0.02±0.15 to 0.31. Ranges of mean ADC difference±limits of agreement (in 10−3mm2/s) for intra-observer agreement were 0.00 to 0.04±0.13 to 0.32.Conclusion: In conclusion, in light of previously reported data, the results of the present study suggest that ADC measurements may not always be sufficiently reproducible to discriminate malignant from non-malignant lymph nodes. Future studies which directly compare the ADCs of different nodal pathologies/conditions are required to further investigate the inter- and intra-observer reproducibilities of ADC measurements of lymph nodes.

Partial volume effects in dynamic contrast magnetic resonance renal studies

2010-08-01

Abstract: This is the first study of partial volume effect in quantifying renal function on dynamic contrast enhanced magnetic resonance imaging. Dynamic image data were acquired for a cohort of 10 healthy volunteers. Following respiratory motion correction, each voxel location was assigned a mixing vector representing the ‘overspilling’ contributions of each tissue due to the convolution action of the imaging system's point spread function. This was used to recover the true intensities associated with each constituent tissue. Thus, non-renal contributions from liver, spleen and other surrounding tissues could be eliminated from the observed time–intensity curves derived from a typical renal cortical region of interest. This analysis produced a change in the early slope of the renal curve, which subsequently resulted in an enhanced glomerular filtration rate estimate. This effect was consistently observed in a Rutland–Patlak analysis of the time–intensity data: the volunteer cohort produced a partial volume effect corrected mean enhancement of 36% in relative glomerular filtration rate with a mean improvement of 7% in r2 fitting of the Rutland–Patlak model compared to the same analysis undertaken without partial volume effect correction. This analysis strongly supports the notion that dynamic contrast enhanced magnetic resonance imaging of kidneys is substantially affected by the partial volume effect, and that this is a significant obfuscating factor in subsequent glomerular filtration rate estimation.

The utility of multi-detector computed tomography in the diagnosis of malignant pleural effusion in the patients with ovarian cancer

2010-08-01

Abstract: Purpose: The purpose of this study was to retrospectively assess possible clinical predictors of malignant pleural effusion in patients with ovarian cancer.Materials and methods: This review was performed on 38 ovarian cancer patients that showed pleural effusion in a CT scan and who underwent thoracocentesis before treatment. CT scans were obtained using a 4-channel multi-detector CT scanner. Fisher's exact test was used to determine the probability of malignant pleural effusion as a function of; amount of ascites, lymph node enlargement, amount of pleural effusion, pleural nodules, and pleural thickening.Results: Sixteen (42.1%) of the 38 patients had malignant pleural effusion and malignant pleural effusion amounts were greater than those with nonmalignant effusion.Pleural nodules were more frequently found in the malignant pleural effusion group (eight [50%] patients) than in the nonmalignant group (zero [0%] patient) (p<0.001). Supradiaphragmatic lymph node enlargement (with short axis diameter 1cm or more) was more frequent in malignant group (12 [75%] patients) than in the nonmalignant group (two [9.1%] patients) (p<0.001).Conclusion: The probability of malignant pleural effusion in patients with ovarian cancer was found to be correlated with the amount of pleural effusion, the presence of pleural nodules, and supradiaphragmatic lymph node enlargement.

MRI findings of spinal visceral larva migrans of Toxocara canis

2010-08-01

Abstract: Purpose: The purpose of this study is to investigate the MRI findings of visceral larva migrans (VLS) of Toxocara canis in spinal cord.Materials and methods: We retrospectively reviewed spinal MRI findings in eight patients with serologically proven Toxocara canis between 2005 and 2008.We evaluated the location, length, extent and migration of the lesion, MR signal intensity (SI), enhancement pattern, and swelling of the spinal cord.We evaluated clinical features including presenting symptoms and signs and treatment response.Results: Total 8 patients (M=8; age range 36–79 years) were included. The lesions were located in the cervical or thoracic spinal cord in all patients. All lesions showed high SI and minimal or mild swelling of involved spinal cord on T2WI and focal nodular enhancement on posterior or posterolateral segment of spinal cord. The length of involved lesion was relatively short in most patients. There was a migration of lesion in one patient.In spite of albendazole or steroid treatment, neurological symptoms or signs were not significantly improved in all patients.Conclusion: Although all lesions show non-specific imaging findings like non-tumorous myelopathy mimicking transverse myelitis, single lesion, focal nodular enhancement on posterior or posterolateral segment of spinal cord, relatively short segmental involvement and migration of lesion may be characteristic findings of spinal VLM of Toxocara canis. In addition, the reluctant response to the treatment may be characteristic of spinal VLM of Toxocara canis.

Facilitating cartilage volume measurement using MRI

2010-08-01

Abstract: Purpose: To compare quantitative cartilage volume measurement (CVM) using different slice thicknesses.Materials and methods: Ten knees were scanned with a 1.5T MRI (Sonata, Siemens, Erlangen, Germany) using a 3D gradient echo sequence (FLASH, fast low-angle shot). Cartilage volume of the medial and lateral tibial plateau was measured by two independent readers in 1.5mm, 3.0mm and 5.0mm slices using the Argus® software application. Accuracy and time effectiveness served as control parameters.Results: Determining cartilage volume, time for calculation diminished for the lateral tibial plateau from 384.6±127.7s and 379.1±117.6s to 214.9±109.9s and 213.9±102.2s to 122.1±60.1s and 126.8±56.2s and for the medial tibial plateau from 465.0±147.7s and 461.8±142.7s to 214.0±67.9s and 208.9±66.2s to 132.6±41.5s and 130.6±42.0s measuring 1.5mm, 3mm and 5mm slices, respectively. No statistically significant difference between cartilage volume measurements was observed (p>0.05) while very good inter-reader correlation was evaluated.Conclusion: CVM using 1.5mm slices provides no higher accuracy than cartilage volume measurement in 5mm slices while an overall time saving up to 70% is possible.

Portal venous diameter in children: Normal limits according to age, weight and height

2010-08-01

Abstract: Purpose: To establish the normal limits of portal vein diameter according to age, height and weight.Materials and methods: One hundred and sixty-eight healthy children, ages ranging from 1 month to 15 years were examined by ultrasound. Portal vein diameters at hepatic port, weight and height were recorded.Results: A range of normal limits for portal veneous diameter according to age, weight and height are obtained and presented in tables.Conclusion: Knowing the normals for portal venous diameter in every age group in children is mandatory in differentiating disease. The tables according to age, weight and height will definitely be helpful in the work-up process.

Limitation for performing ultrasound-guided radiofrequency ablation of small renal masses

2010-08-01

Abstract: Purpose: To evaluate which factor is involved in limiting ultrasound (US)-guided radiofrequency (RF) ablation of small renal masses.Materials and methods: Twenty-five patients with 31 renal masses underwent image-guided RF ablation. If a lesion was visible on US, US-guided RF ablation was performed. If a lesion was invisible on US or if the lesion was incompletely ablated or recurred following US-guided RF ablation, CT-guided RF ablation was performed. We analyzed the various factors which were involved in US-guided RF ablation.Results: Of 31 masses, thirteen were US-visible lesions and underwent US-guided RF ablation whereas thirteen were US-invisible lesions and thus underwent CT-guided RF ablation. The remaining five lesions were US-visible but needed additional CT-guided RF ablation, due to incomplete ablation (n=4) or recurrence (n=1); these renal masses (3.1±1.0cm) were significantly larger than those (1.8±0.6cm) ablated with US alone (p<0.05). Steam bubbles (4.4cm±0.7cm) of the masses requiring additional CT-guided RF ablation were significantly larger than those (2.9cm±0.7cm) of the tumors completely ablated with US alone in size (p<0.05).Conclusions: US-invisibility, lesion size, and steam bubbles may limit to perform US-guided RF ablation of small renal masses.

Ultrasonography-guided percutaneous radiofrequency ablation of hepatocellular carcinomas: A feasibility scoring system for planning sonography

Hyunchul Rhim, Dongil Choi, Young-sun Kim, Hyo K. Lim, Bong-Keun Choe — 2010-08-01

Abstract: Purpose: This study was designed to evaluate whether a feasibility scoring system for planning sonography is a reliable predictor of a safe and complete ablation in ultrasonography (US)-guided percutaneous radiofrequency ablation (RFA) of hepatocellular carcinomas (HCCs).Materials and methods: We retrospectively evaluated the therapeutic outcomes of 108 consecutive patients (M:F, 78:30; mean age, 57.4 years) with a single nodular HCC (mean diameter, 2.0cm) treated by percutaneous RFA. All patients were assessed for the feasibility of performing an RFA at planning sonography prior to the ablation. The feasibility scoring system consisted of five categories: the safe electrode path (P); the vital organs adjacent to the RFA zone (O); tumor size (S); tumor conspicuity (C); and the heat-sink effect (H). Each category was divided into a four-point scale [1–4]. If a score of 4 in any category was determined, the patient was not considered to be a suitable candidate for percutaneous RFA. We assessed if the score of each category, safety score (P+O), and curability score (S+C+H) correlated with a safe and complete ablation using the chi-squared test and likelihood ratio test for trend.Results: The technical success rate was 100% (108/108) based on CT images obtained immediately after ablation. There was no 30-day mortality after RFA. There were major complications (one case of severe vasovagal reflex, one case of hemoperitoneum and one case of a pseudoaneurysm) in three (2.7%) patients, and minor complications (one case of a biloma, one case of subsegmental infarction and one case of abscess) in three (2.7%) patients. Post-ablation syndrome as a side effect was noted in 38 (35.1%) of 108 patients. The primary technique effectiveness rate at 1 month was 95.1% (105/108). Local tumor progression was noted in eight (7.6%) of 105 patients during the follow-up period (range, 3.0–11.5 months; median, 5.8 months; mean, 5.7 months). There was no significant single category to predict complication and local tumor progression (Fisher's exact test, p>0.05). Contrary to the safety score for the probability of complication (p>0.05), the curability score was significantly associated with the probability of local tumor progression (likelihood ratio test for trend; p=0.03).Conclusion: The new feasibility scoring system for planning US can be used as objective criteria to predict therapeutic efficacy rather than the safety of percutaneous RFA of an HCC.

Radiation effects analysis in a group of interventional radiologists using biological and physical dosimetry methods

2010-08-01

Abstract: Interventional radiologists and staff members are frequently exposed to protracted and fractionated low doses of ionizing radiation, which extend during all their professional activities. These exposures can derive, due to the effects of direct and scattered radiation, in deterministic effects (radiodermitis, aged skin, cataracts, telangiectasia in nasal region, vasocellular epitelioms, hands depilation) and/or stochastic ones (cancer incidence). A methodology has been proposed for estimating the radiation risk or detriment from a group of six exposed interventional radiologists of the Hospital Universitario La Fe (Valencia, Spain), which had developed general exposition symptoms attributable to deterministic effects of ionizing radiation. Equivalent doses have been periodically registered using TLD’s and wrist dosimeters, Hp(10) and Hp(0.07), respectively, and estimated through the observation of translocations in lymphocytes of peripheral blood (biological methods), by extrapolating the yield of translocations to their respective dose–effect curves. The software RADRISK has been applied for estimating radiation risks in these occupational radiation exposures. This software is based on transport models from epidemiological studies of population exposed to external sources of ionizing radiation, such as Hiroshima and Nagasaki atomic bomb survivors [UNSCEAR, Sources and effects of ionizing radiation: 2006 report to the general assembly, with scientific annexes. New York: United Nations; 2006]. The minimum and maximum average excess ratio for skin cancer has been, using wrist physical doses, of [, ], concluding that there is not an increased risk of skin cancer incidence. The minimum and maximum average excess ratio for leukemia has been, using TLD physical doses, of [, ], and using biological doses, of [, 1.51], which is considerably higher than incidence rates, showing an excess radio-induced risk of leukemia in the group under study. Finally, the maximum radiological detriment in the group, evaluated as the total number of radio-induced cancers using physical dosimetry, has been of 2.18/1000 person-year (skin and leukemia), and using biological dosimetry of 9.20/1000 PY (leukemia). As a conclusion, this study has provided an assessment of the non-deterministic effects (rate of radio-induced cancer incidence) attributable to the group under study due to their professional activity.

A comparative evaluation of Cone Beam Computed Tomography (CBCT) and Multi-Slice CT (MSCT) Part I. On subjective image quality

2010-08-01

Abstract: Aims: To compare image quality and visibility of anatomical structures in the mandible between five Cone Beam Computed Tomography (CBCT) scanners and one Multi-Slice CT (MSCT) system.Materials and methods: One dry mandible was scanned with five CBCT scanners (Accuitomo 3D, i-CAT, NewTom 3G, Galileos, Scanora 3D) and one MSCT system (Somatom Sensation 16) using 13 different scan protocols. Visibility of 11 anatomical structures and overall image noise were compared between CBCT and MSCT. Five independent observers reviewed the CBCT and the MSCT images in the three orthographic planes (axial, sagittal and coronal) and assessed image quality on a five-point scale.Results: Significant differences were found in the visibility of the different anatomical structures and image noise level between MSCT and CBCT and among the five CBCT systems (p=0.0001). Delicate structures such as trabecular bone and periodontal ligament were significantly less visible and more variable among the systems in comparison with other anatomical structures (p=0.0001). Visibility of relatively large structures such as mandibular canal and mental foramen was satisfactory for all devices. The Accuitomo system was superior to MSCT and all other CBCT systems in depicting anatomical structures while MSCT was superior to all other CBCT systems in terms of reduced image noise.Conclusions: CBCT image quality is comparable or even superior to MSCT even though some variability exists among the different CBCT systems in depicting delicate structures. Considering the low radiation dose and high-resolution imaging, CBCT could be beneficial for dentomaxillofacial radiology.

A comparative evaluation of Cone Beam Computed Tomography (CBCT) and Multi-Slice CT (MSCT). Part II: On 3D model accuracy

2010-08-01

Abstract: Aim: The study aim was to compare the geometric accuracy of three-dimensional (3D) surface model reconstructions between five Cone Beam Computed Tomography (CBCT) scanners and one Multi-Slice CT (MSCT) system.Materials and methods: A dry human mandible was scanned with five CBCT systems (NewTom 3G, Accuitomo 3D, i-CAT, Galileos, Scanora 3D) and one MSCT scanner (Somatom Sensation 16). A 3D surface bone model was created from the six systems. The reference (gold standard) 3D model was obtained with a high resolution laser surface scanner. The 3D models from the five systems were compared with the gold standard using a point-based rigid registration algorithm.Results: The mean deviation from the gold standard for MSCT was 0.137mm and for CBCT were 0.282, 0.225, 0.165, 0.386 and 0.206mm for the i-CAT, Accuitomo, NewTom, Scanora and Galileos, respectively.Conclusion: The results show that the accuracy of CBCT 3D surface model reconstructions is somewhat lower but acceptable comparing to MSCT from the gold standard.

Normal and accessory fissures of the lung: Evaluation with contiguous volumetric thin-section multidetector CT

2010-08-01

Abstract: The purpose of this study was to use volumetric, 1.25mm collimation MDCT read as softcopy and using a 2D and 3D viewer tool, to establish the frequency of normal and accessory fissures, the continuity of the fissures, whether the fissures are visible as a thin line, a hypovascular region, or both, and also to establish the interobserver agreement of readers. 150 consecutive MDCT examinations were retrospectively assessed. Interobserver agreement for each of these fissures was evaluated using the Kappa statistic. All subjects had a right and a left major fissure. 96.7% of subjects also had a right minor fissure. 40% had an accessory fissure, the most common, the left minor in 16% of subjects. Most of the three usual fissures were continuous, whereas fewer than half of accessory fissures were continuous. The majority (54–100%) of normal and accessory fissures were visualized as a thin line. There was substantial to excellent interobserver agreement on the presence or absence of fissures their continuity (k=0.96), and fair to excellent agreement on fissure morphology (k=0.37–1.0). The prevalence of fissures on MDCT, equivalent to autopsy studies, visualizing fissures as a thin line and high interobserver agreement is probably due to the high sensitivity of MDCT, secondary to thin-section volumetric imaging.

Magnetic resonance imaging of breast vascularity in medial versus lateral breast cancer

A. Grubstein, M. Yepes, R. Kiszonas — 2010-08-01

Abstract: Objective: Breasts with malignant tumors can demonstrate a general increased vascularity compared to the contralateral breast and a prominent blood vessel adjacent to the tumor on magnetic resonance imaging (MRI). The aim of the study was to further characterize these alterations in blood supply by location of the tumor within the breast using MRI.Materials and methods: The study group included 105 patients who underwent breast MRI for suspicion of a malignancy over a 2-year period. Fifty-one had pathologically verified malignant tumors (study group), 11 had pathologically verified benign lesions (control), and 43 had negative scans (control). The malignant lesions were distinguished by location, medial or lateral, within the breast. Origin of the vascular supply and vessel diameter was recorded in a blinded manner. When available, MRI scans performed 2 years after treatment were reviewed as well.Results: Of the 24 medial malignant tumors, 21 (87%) had a predominantly medial vascular supply and 3 (13%), a predominantly lateral supply; of the 23 lateral tumors, 11 (48%) had a predominantly medial vascular supply and 8 (35%), a predominantly lateral supply (p=0.03). In 4 cases, no dominant vessel was noted. Maximum vessel diameter was 3.6±1.1mm in the patients with malignancy and 2.6±0.8mm in the controls (p<0.0005). General increased vascularity was demonstrated in 91% of the medial tumor subgroup and 83% of the lateral tumor subgroup, as opposed to 36–37% in the control groups (p<0.0005). Follow-up MRI, performed in 8 patients in the malignant-tumor group after treatment, revealed a considerable decrease in the prominent vessels, to a size close to that of the controls.Conclusion: Breasts with malignant tumors are characterized by an altered general vascular supply, a prominent feeding vessel, and increased regional vascularity. Both the presence and location of the tumor affect the vascular supply. The vascular change apparently diminishes after treatment, although this finding requires further investigation in a larger sample.

Diagnostic performance of radiographers as compared to radiologists in magnetic resonance colonography

2010-08-01

Abstract: Purpose: To evaluate the diagnostic performance of radiographers compared to radiologists in the detection of colorectal lesions in MR colonography.Material and methods: 159 patients at increased risk of colorectal cancer were included. Four different experienced observers, one MR radiologist, one radiologist in training and two radiographers evaluated all MR colonography examinations. The protocol included T1-weighted and T2-weighted sequences in prone and supine position. Colonoscopy was used as reference standard. Mean sensitivity rates with 95% confidence intervals (CIs) were determined on a per-patient and per-polyp basis, segmented by size (≥6mm and ≥10mm). Specificity was calculated on a per-patient basis. The McNemar and chi-square (χ2) test was used to determine significant differences.Results: At colonoscopy 74 patients (47%) had normal findings; 23 patients had 40 polyps with a size ≥6mm. In 10 patients at least 1 polyp ≥10mm was found (20 polyps in total). Similar sensitivities for patients with lesions ≥10mm were found for radiologists and radiographers (65% (95%CI: 44–86%) vs. 50% (95%CI: 28–72%)) (p=n.s.). For lesions ≥10mm combined per-patient specificity for radiologists and radiographers was 96% (95%CI: 94–98%) and 73% (95%CI: 68–79%) (p<0.0001). Combined per-patient sensitivity for lesions ≥6mm differed significantly between both groups of observers (57% (95%CI: 42–71%) vs. 33% (95%CI: 19–46%)) (p=0.03).Conclusion: Radiographers have comparable sensitivity but lower specificity relative to radiologists in the detection of colorectal lesions ≥10mm at MR colonography. Adequate training in evaluating MR colonography is necessary, especially for readers with no prior experience with colonography.

Value of ductal obstruction sign in the differentiation of benign and malignant breast lesions at MR imaging

2010-08-01

Abstract: Purpose: : MR-Mammography (MRM) is regarded as the most sensitive method for detection of breast cancer without a broad consensus on specificity. There is room for improvement of the existing ACR BIRADS lexicon by adding new and specific descriptors. Dilated ducts have been described in association with papillomas. However, the differential diagnostic value of this finding has not been investigated yet.Materials and methods: : 316 consecutive patients, undergoing histopathologic workup after MR-Mammography were included in this prospective, ethical review board approved study. Two blinded radiologists rated the images in consensus. Ductal obstruction was defined as dilated liquid filled ducts proximal an enhancing lesion. Sensitivity, specificity as well as positive and negative likelihood ratio (LR+, LR−) were calculated.Results: Dilated ducts were found in 60 cases (19%), 20 of these showed an association with enhancing lesions and were categorized as ductal obstruction (6.3%). Malignancy was found in two cases (one invasive ductal carcinoma and one DCIS) and benign tissue in 18 cases (15 papillomas). The difference of ductal obstruction between these groups was found to be highly significant in two-sided Fisher's exact test (p<0.001).Because of the clear association with benign lesions, benign lesions showing ductal obstruction were characterized as true positive findings. Therefore, following diagnostic parameters were calculated: sensitivity 15.4%, specificity 99.0%, LR+ 15.3, LR− 0.9.Discussion: If ductal obstruction is found to be positive, the associated lesion is most likely benign. Therefore, though a rare finding, this descriptor should be taken into account for improved lesion differentiation.

Software-based quantification of contrast-enhanced ultrasound in focal liver lesions—A feasibility study

2010-08-01

Abstract: Purpose: To compare software-based quantification of contrast-enhanced ultrasound (CEUS) examinations of focal liver lesions in the arterial and late phases with the enhancement patterns established by the sonologist.Materials and methods: The study cohort comprised 12 malignant and 21 benign hepatic lesions in 33 patients (18 female and 15 male; aged 57±13 years). All underwent dynamic real-time low mechanical index (<0.3) CEUS, which was stored as video sequences of the various enhancement phases. A software was used for analysis by using different regions of interest (ROI) in a double-blinded manner. The software generated and the visual enhancement patterns were compared, and the t-test was performed.Results: The videos containing the arterial phase had a mean length of 37.5±36.7s and the late phase sequences a mean length of 15.2±9.2s. In the arterial phase complete agreement between software and sonologist was 100%, 93.9% and 87.9% with regard to the entire lesion, its centre and its periphery, respectively. The late phase analysis revealed corresponding figures of 90.9%, 87.9% and 90.9%. In the late phase, benign lesions revealed a mean relative enhancement of +65.1±103.6% and malignant lesions −56.9±26.3% (p=0.0005) vis-à-vis liver parenchyma. All the malignant and 14% of the benign tumors showed hypo-enhancement of less than −10%.Conclusion: The complete agreement between the quantitative analysis and the sonologist within the arterial and late phase showed excellent results. Software analysis of the late phase could dichotomise benign and malignant lesions. Objective establishment of iso-enhancement in the late phase excludes malignancy.

Hypothenar hammer syndrome: Long-term follow-up of selective thrombolysis by 3.0-T MR angiography

2010-08-01

Abstract: Objective: To assess the long-term outcome of selective thrombolysis in patients with hypothenar hammer syndrome by 3.0-T magnetic resonance (MR) angiography.Materials and methods: Seven patients (6 men, 1 woman; mean age, 58.6±14.4 years) were investigated. Long-term follow-up examinations (9–11 years post-interventional) were based on 3.0-T MR angiography. Pre- versus post-thrombolysis images and post-thrombolysis versus long-term follow-up images were compared with respect to arterial diameter. Additionally, changes in patients’ symptoms were assessed.Results: The long-term follow-up examination showed worse contrast filling of the ulnar digits compared to the immediately post-interventional angiographic images only in one patient (14.3%), whereas worse contrast filling of the deep palmar arch or the ulnar artery was registered in three patients (42.9%). Three of seven patients (42.9%) reported worse symptoms, two patients (28.6%) stable symptoms at the long-term follow-up MR angiography. In two patients (28.6%) the change of symptoms could not be observed due to missing post-interventional clinical data.Conclusions: At the long-term follow-up, clinically, mild progression was found rather often, whereas with respect to imaging findings progression at the ulnar digits was rare. We assume that collateral vessels might play a major role in the post-interventional follow-up. In many instances the patients’ symptoms are not in line with the angiographic findings.

Pre-treatment hemodynamic features involved with long-term survival of cirrhotic patients after embolization of gastric fundal varices

2010-08-01

Abstract: Purpose: To clarify the pre-treatment hemodynamic features involved in the long-term survival of cirrhotic patients with gastric fundal varices (FV) after balloon-occluded retrograde transvenous obliteration (B-RTO).Materials and methods: Eighty-one cirrhotic patients with medium- or large-grade FV treated by B-RTO were enrolled in this retrospective study. Pre-treatment flow volume ratio between gastric vein and portal trunk (GP-R) was obtained by Doppler ultrasound.Results: The cumulative survival rate was 90% at 1 year, 74.8% at 3 years, 57.2% at 5 years, and 45.8% at 7 years without recurrence in a median period of 1148.5 days The survival was poorer in patients with HCC (47% at 3 years, 9.4% at 5 years, p<0.0001) than without (89.2% at 3 years, 81.9% at 5 years, 67.5% at 7 years), in patients with Child B/C (57.7% at 3 years, 42.1% at 5 years, 28.1% at 7 years, p=0.0016) than with Child A (91.8% at 3 years, 71.5% at 5 years, 62.1% at 7 years), and in patients with GP-R≥1.0 (58.9% at 3 years, p=0.0485) than with GP-R<1.0 (76.3% at 3 years, 62% at 5 years, 49.6% at 7 years). Multivariate analysis identified the presence of HCC (hazard ratio, 12.486; 95% CI, 4.08–38.216; p<0.0001), Child B/C (hazard ratio, 3.41; 95% CI, 1.594–7.15; p=0.0051) and GP-R≥1.0 (hazard ratio, 2.701; 95% CI, 1.07–6.15; p=0.0221) as independent factors for poor prognosis.Conclusion: GP-R≥1.0 on Doppler ultrasound before B-RTO may be a predictive indicator for poor prognosis in cirrhotic patients with FV after B-RTO, in addition to the presence of HCC and severe liver damage.

Secretin-stimulated MR cholangio-pancreatography in the evaluation of asymptomatic patients with non-specific pancreatic hyperenzymemia

2010-08-01

Abstract: Purpose: To assess the diagnostic value of secretin-stimulated MRCP (SS-MRCP) compared with conventional MRCP in asymptomatic patients with mild elevations of pancreatic enzymes.Materials and methods: Eighty asymptomatic patients with pancreatic hyperenzymemia underwent MR imaging at 1.5T-device (Signa EXCITE, GE Healthcare). After the acquisition of axial T1w,T2w sequences, and conventional MRCP, SS-MRCP was performed using a single-slice coronal breath-hold, thick-slab, SSFSE T2w sequence, repeated every 30s up to 15min following intravenous injection of secretin (Secrelux®, Sanochemia).Results: On the basis of the standards of reference, our final diagnoses were: negative findings (n=23), pancreas divisum (n=22), mild chronic pancreatitis (n=14), inflammatory ampullary stenosis (n=3), juxtapapillary duodenal diverticulum (n=1), small cystic lesions (<1cm) (n=22; 5/22 cases associated with pancreas divisum). The image quality of SS-MRCP was significantly higher than that of conventional MRCP (p<0.0001). Standards of reference did not differ significantly from of SS-MRCP findings (p=0.5), while was statistically different from those of conventional MRCP (p<0.0001). A significant difference was found between conventional MRCP and SS-MRCP findings (p<0.0001).Conclusion: In asymptomatic patients with non-specific pancreatic hyperenzymemia SS-MRCP may represent the best non-invasive diagnostic technique, since it gives morphological and functional information.

CT imaging spectrum of pancreatic serous tumors: Based on new pathologic classification

2010-08-01

Abstract: Purpose: The aim of this study is to retrospectively analyze the variety of CT findings based on new pathologic classification.Materials and methods: During a 10-year period, 59 histopathologically proven pancreatic SCTs and 13 SCTs confirmed with typical image findings and strict clinical criteria were enlisted. Two radiologists analyzed CT images for the following items in consensus: location, size, outer margin, tumor shape, the presence of mural nodule, communication with main pancreatic duct (MPD), the presence and extent of MPD dilatation, calcification, central scar, and attenuation on pre- and post-contrast CT images. In addition, typicality of CT findings was determined. A typical finding was defined as a honeycomb appearance without or with oligocystic portion. In the cases with atypical features, the type of atypical features and differential diagnosis were recorded. For the shape of the tumor, tumors were categorized into the following groups: honeycomb without or with oligocystic, pleomorphic, purely oligolocular, unilocular cystic, hypovascular solid, hypervascular solid without or with oligocystic portion, and fingerlike cystic patterns.Results: 28 SCTs (38.9%) presented a honeycomb appearance with (n=14) or without oligocystic portion (n=14) and were classified as typical cases. The remaining 44 atypical cases (61.1%) presented the following: purely oligolocular pattern in 18; hypervascular solid without (n=7) or with oligocystic portion (n=2) in 9; pleomorphic in 8; unilocular cystic in 7; and fingerlike cystic pattern in 2. Most of the lesions manifesting as hypervascular solid lesions were confused with true solid hypervascular tumors such as neuroendocrine tumors or solid pseudopapillary tumors. For most of the remaining atypical lesions, mucinous cystic neoplasm or branch duct type IPMN were included as a differential diagnosis.Conclusion: Serous cystic tumors of the pancreas can have variable CT appearances ranging from compactly solid hypervascular to clearly unilocular cystic, which reflect a varied macroscopic morphology. Only 38.9% of the SCTs show traditional typical CT features whereas a considerable proportion (61.1%) of SCTs showed atypical appearances, providing diagnostic challenges to radiologists.

MR pelvimetry measurements, analysis of inter- and intra-observer variation

U. Korhonen, R. Solja, J. Laitinen, S. Heinonen, P. Taipale — 2010-08-01

Abstract: Objective: To set reference standards and then to evaluate the measurement variation in magnetic resonance (MR) pelvimetry between observations and observers.Methods: The study was carried out retrospectively using 100 MR pelvimetry examinations performed in North Carelian Central Hospital between September 2006 and January 2008. Pelvimetric parameters of pelvic inlet and outlet were measured four times to determine the standard reference for each measurement and then intra- and inter-observer variations were compared.Results: The accuracy of MR pelvimetry, defined as a deviation of <5mm from the reference standard, was better in pelvic inlet measurements than in the corresponding outlet measurements (95–99% vs. 86–89%). Intra-observer variation was acceptable in all of the measurements with intraclass correlation coefficient (ICC) in the range 0.956–0.981 in all parameters. Inter-observer variation was higher than intra-observer variation. The largest variation of measurements was in pelvic outlet parameters between observers with the ICC in the range of 0.710–0.813.Conclusion: MR pelvimetry measurement should be conducted in a centralized location to decrease observer-related variation. Clinicans should be aware that millimeter differences are not reliable in MR pelvimetry and therefore the use of millimeter accurate limits are not recommended in obstetric decision making.

Correlation of 18F-fluorodeoxyglucose uptake on positron emission tomography with Ki-67 index and pathological invasive area in lung adenocarcinomas 30mm or less in size

2010-08-01

Abstract: Background: 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is commonly used to distinguish benign from malignant lesion. Recently, maximum standardized uptake value (SUVmax) on FDG-PET has found to have prognostic value. We examined the relationship between SUVmax and proliferative activities as indicated by maximum diameter of tumor opacity on mediastinal-window images (TOM), Ki-67 index, and diameter of the pathological invasive area in lung adenocarcinomas ≤30mm.Methods: Thin-section computed tomography (TS-CT) and FDG-PET were performed on 140 patients with resectable lung adenocarcinomas ≤30mm between March 2006 and May 2008. Tumors were classified as air-type or solid-type based on TS-CT findings. In all resected specimens, diameter of the pathological invasive area and Ki-67 index were assessed.Results: SUVmax was significantly lower for air-type than for solid-type tumors (0.97 vs. 3.96, p<0.0001). In solid-type tumors, SUVmax correlated with diameter of TOM (r=0.450, p<0.0001), Ki-67 index (r=0.567, p<0.0001), and diameter of the pathological invasive area (r=0.672, p<0.0001). In multiple regression analysis, SUVmax correlated significantly with Ki-67 index and diameter of the pathological invasive area but not with diameter of TOM. The cut-off value of SUVmax for predicting invasive area >5mm was determined as 2.15 by ROC analysis, with sensitivity of 88.3% and specificity of 84.6%.Conclusions: SUVmax correlated significantly with Ki-67 index and diameter of the pathological invasive area. The present results suggest the potential role of FDG-PET in predicting adenocarcinomas with invasive characteristics.

Evaluation of the therapeutic efficacy of high-intensity focused ultrasound ablation of hepatocellular carcinoma by three-dimensional sonography with a perflubutane-based contrast agent

2010-08-01

Abstract: Objective: We performed contrast-enhanced three-dimensional sonography (CE 3D US) with a perflubutane-based contrast agent to immediately evaluate the completeness of ablation of small hepatocellular carcinoma (HCC) lesions by extracorporeal high-intensity focused ultrasound (HIFU).Subjects and methods: Twenty-one HCC lesions were treated by a single ultrasound-guided HIFU ablation session, and CE 3D US was performed before, immediately after, and 1 week, and 1 month after HIFU, and contrast-enhanced CT (CE CT) or contrast-enhanced MRI (CE MRI) was performed before HIFU, 1 week and 1 month after HIFU, and during the follow-up period.Results: Immediately and 1 month after HIFU, 17 lesions were evaluated as adequately ablated by CE 3D US, and the other 4 lesions as residual tumors. One month after HIFU, 18 were evaluated as adequately ablated by CE CT or CE MRI, and the other 3 as residual tumors. The evaluation by CE 3D US immediately after HIFU and by CE CT or CE MRI 1 month after HIFU was concordant with 20 lesions. The kappa value for agreement between the findings of CE 3D US and other modalities by two blinded observers was 0.83. When the 1-month CE CT or CE MRI findings were used as the reference standard, the sensitivity, specificity, and accuracy of CE 3D US immediately after HIFU for the diagnosis of the adequate ablation were 100%, 75%, and 95%, respectively.Conclusion: CE 3D US appears to be a useful method for immediate evaluation of therapeutic efficacy of HIFU ablation of HCC lesions.

Influence of fluid-attenuated inversion-recovery on stroke apparent diffusion coefficient measurements and its clinical application

2010-08-01

Abstract: Background and purpose: The application of a fluid-attenuated inversion-recovery pulse with a conventional diffusion-weighted MRI sequence (FLAIR DWI) decreases the partial volume effects from cerebrospinal fluid on apparent diffusion coefficient (ADC) measurements. For this reason, FLAIR DWI may be more useful in the evaluation of ischemic stroke, but few studies have looked at the effect of FLAIR on ADC measurements in this setting. This study quantitatively compares FLAIR DWI and conventional DWI in ischemic stroke of varying ages to assess the potential advantages of this technique.Methods: We respectively analyzed 139 DWI studies in patients with ischemic stroke with and without FLAIR at varying time points ranging from hyperacute to chronic. ADC values were measured in each lesion, as well as in the contralateral normal side. Comparisons were made between the ADC values obtained from the DWI sequences with and without FLAIR for both the lesion and the normal contralateral side.Results: The ADC measurements within the ischemic lesion were very similar on FLAIR DWI and conventional DWI for lesions less than 14 days old (p>0.05), but were significantly decreased on FLAIR DWI for lesions between 15 and 30 days old and in lesions >31 days old (chronic stage) (p<0.01). The contralateral ADC values were all significantly decreased on the FLAIR DWI sequence compared with conventional DWI (p<0.01).Conclusions: The application of an inversion pulse does not significantly affect the ADC values for early stage ischemic stroke (less than 14 days from symptom onset), but results in a more accurate relative ADC measurement by reducing the cerebrospinal fluid partial volume effects of the normal contralateral side. In addition, combined with the conventional DWI, FLAIR DWI may be helpful in determining the age of ischemic lesions.

MR imaging of the knee: Improvement of signal and contrast efficiency of T1-weighted turbo spin echo sequences by applying a driven equilibrium (DRIVE) pulse

2010-08-01

Abstract: The purpose of this study was to assess the effect of a driven equilibrium (DRIVE) pulse incorporated in a standard T1-weighted turbo spin echo (TSE) sequence as used in our routine MRI protocol for examination of pathologies of the knee.Sixteen consecutive patients with knee disorders were examined using the routine MRI protocol, including T1-weighted TSE-sequences with and without a DRIVE pulse. Signal-to-noise ratios (SNRs) and contrast-to-noise ratio (CNR) of anatomical structures and pathologies were calculated and compared for both sequences. The differences in diagnostic value of the T1-weighted images with and without DRIVE pulse were assessed.SNR was significantly higher on images acquired with DRIVE pulse for fluid, effusion, cartilage and bone. Differences in the SNR of meniscus and muscle between the two sequences were not statistically significant. CNR was significantly increased between muscle and effusion, fluid and cartilage, fluid and meniscus, cartilage and meniscus, bone and cartilage on images acquired using the DRIVE pulse. Diagnostic value of the T1-weighted images was found to be improved for delineation of anatomic structures and for diagnosing a variety of pathologies when a DRIVE pulse is incorporated in the sequence.Incorporation of a DRIVE pulse into a standard T1-weighted TSE-sequence leads to significant increase of SNR and CNR of both, anatomical structures and pathologies, and consequently to an increase in diagnostic value within the same acquisition time.

Correlation between myocardial fibrosis and the occurrence of atrial fibrillation in hypertrophic cardiomyopathy: A cardiac magnetic resonance imaging study

2010-08-01

Abstract: Cardiac magnetic resonance imaging (CMR) in hypertrophic cardiomyopathy (HCM) often shows delayed contrast enhancement (DE) representing regions of focal myocardial fibrosis. Atrial fibrillation (AF) is a commonly reported complication of HCM. We determined the relationship between the presence of left ventricular myocardial fibrosis (LVMF) detected by DE-CMR and the occurrence AF in a series of patients with HCM. 67 patients with HCM (47 males; mean age 50.1±18.5 years) were studied by CMR measuring mass of LVMF, left ventricular mass, volume and function, and left atrial (LA) area. AF was present in 17 (25%) patients. LVMF was observed in 57% of patients. AF was significantly more frequent in patients who also showed LVMF, compared with the group without LVMF (42.1% vs. 3.4%, respectively; p<0.0001). LA size was larger in patients showing DE (LA area: 37.4±11.1 vs. 25.9±6.8cm2; respectively, p=0.0001). AF in HCM is related with myocardial fibrosis detected by DE-CMR and dilatation of the LA. This fact adds to the proven adverse prognostic value of myocardial fibrosis in HCM, thus, reinforcing the usefulness of this technique in the assessment of these patients.

Asymmetric spermatic cord vessel enhancement and enlargement on contrast-enhanced MDCT as indicators of ipsilateral scrotal pathology

Paras Lakhani, Nicholas Papanicolaou, Parvati Ramchandani, Drew A. Torigian — 2010-08-01

Abstract: Purpose: To determine the association of asymmetric spermatic cord vessel enhancement and enlargement on contrast-enhanced CT with ipsilateral scrotal pathology.Methods: This case series included 30 men with contrast-enhanced CT: 10 cases had asymmetric enhancement and enlargement of spermatic cord vessels with confirmed ipsilateral scrotal pathology determined by additional imaging and/or clinical records; 20 negative reference cases had no such findings with normal corresponding scrotal ultrasound. Maximum spermatic vessel diameters and attenuation values were determined bilaterally. Two blinded radiologists independently assessed all exams for interobserver agreement.Results: For cases, maximum spermatic cord vessel diameters were greater ipsilaterally (5.9±1.7mm) than contralaterally (4.0±1.1mm), p<0.001. Maximum HU values were greater ipsilaterally (139.5±29.5) than contralaterally (70.6±17.5), p<0.0003. Maximum spermatic vessel diameters and attenuation values were significantly greater for positive than negative reference cases (p<3.9×10−8 and p<4.9×10−7 respectively). There was substantial interobserver agreement for asymmetric spermatic vessel enlargement (κ=0.79) and enhancement (κ=0.73). In 3 cases, the CT findings lead to a scrotal ultrasound that confirmed the diagnosis and altered patient management.Conclusion: MDCT findings of asymmetric spermatic vessel enlargement and enhancement are indicators of ipsilateral scrotal pathology. The detection of such finings may have implications for patient care and should prompt further evaluation of the scrotum in the proper clinical setting.

MR imaging for blunt pancreatic injury

Lin Yang, Xiao Ming Zhang, Xiao Xue Xu, Wei Tang, Bo Xiao, Nan Lin Zeng — 2010-08-01

Abstract: Objective: To study the MR imaging features of blunt pancreatic injury.Materials and methods: Nine patients with pancreatic injury related to blunt abdominal trauma confirmed by surgery performed MR imaging. Two abdominal radiologists conducted a review of the MR images to assess pancreatic parenchymal and pancreatic duct injury, and associated complications.Result: Diagnostic quality MR images were obtained in each of the nine patients. In the nine patients, pancreatic fracture, laceration and contusion were depicted on MR imaging in five, one and three patients, respectively. There were six patients with pancreatic duct disruption, eight patients with peripancreatic fluid collections, and four patients with peripancreatic pseudocyst or hematoma, respectively. All of the MR imaging findings was corresponded to surgical findings.Conclusion: MR imaging is an effective method to detect blunt pancreatic injury and may provide information to guide management decisions.

Hepatic unsaturated fatty acids in patients with non-alcoholic fatty liver disease assessed by 3.0T MR spectroscopy

2010-08-01

Abstract: Rationale and objective: Non-alcoholic fatty liver disease (NAFLD) is related to the metabolic syndrome and obesity. Proton magnetic resonance spectroscopy (1H MRS) is a non-invasive technique to assess hepatic triglyceride content (HTGC) and allows assessment of unsaturated fatty acids (UFA). There is increasing evidence that hepatic UFA are associated with the development of NAFLD. Therefore the objective of this study was to assess hepatic UFA in patients with NAFLD using 1H MRS.Materials and methods: We included 26 consecutive patients with deranged liver enzymes, with and without type 2 diabetes mellitus (DM2), suspected for NAFLD. Liver function and metabolic parameters were assessed. 1H MRS measurements were performed at 3.0T. From the 1H MR spectra two ratios were calculated: ratio 1 (UFA); unsaturated fatty acid peak vs. reference water peak and ratio 2 (HTGC); total fatty acid peak vs. reference water peak.Results: Twenty-six patients were included. In these patients hepatic UFA (ratio 1) correlated with AST/ALT ratio (r=−0.46, p=0.02), glucose levels (r=0.46, p=0.018), HOMA-IR (r=0.59, p=0.004) and HTGC (r=0.81, p<0.001). In diabetic patients (n=12) hepatic UFA correlated with alkaline phosphatase levels (r=0.72, p=0.01), HOMA-IR (r=0.73, p=0.01) and HTGC (r=0.83, p=0.002). Compared to non-diabetic patients with NAFLD, hepatic UFA levels were increased in patients with DM2 and NAFLD (0.032 vs. 0.014, p=0.03).Conclusion: Hepatic UFA can be assessed with 1H MRS. 1H MRS determined hepatic UFA correlate with clinical and metabolic parameters associated with NAFLD. Hepatic UFA are increased in patients with DM2. This study provides evidence for the use of non-invasive 1H MRS to assess hepatic UFA in vivo.

Pain and functional outcome after vertebroplasty and kyphoplasty. A comparative study

2010-08-01

Abstract: Purpose: The aim of this study was to compare the effectiveness of percutaneous vertebroplasty and kyphoplasty to treat pain from non-neoplastic vertebral fractures and improve functional outcomes.Materials and methods: We compared 30 patients treated by vertebroplasty for non-neoplastic vertebral fractures with 30 patients treated by kyphoplasty for the same condition. Pain was measured with a visual analogue scale (VAS) and functional outcome with the Oswestry disability index (ODI). Baseline data were compared with measurements on the day after the procedure (for pain alone) and at 1 month, 6 months, and 1 year.Results: The VAS pain score was reduced by 4–5 points on the day after either type of treatment, a statistically significant improvement. The global ODI was significantly improved (by 13–18 points) at 1 month after either procedure. These improvements persisted at 6 months and 1 year. No significant differences in functional outcome were observed between the techniques.Conclusion: Vertebroplasty and kyphoplasty obtain similar improvements in pain and functional outcomes in these patients. The choice of technique must therefore depend on other factors. An initial improvement with either technique is a good predictor of long-term improvement.

DWI in breast MRI: Role of ADC value to determine diagnosis between recurrent tumor and surgical scar in operated patients

2010-08-01

Abstract: Introduction: Purpose of our study is to evaluate the role of the apparent diffusion coefficient (ADC) in the diagnosis of recurrent tumor on the scar in patients operated for breast cancer. Assess, therefore, the weight of diagnostic diffusion echo-planar sequence, in association with the morphological and dynamic sequences in the diagnosis of tumor recurrence versus surgical scar.Materials and methods: From September 2007 to March 2009, 72 patients operated for breast cancer with suspected recurrence on the scar were consecutively subjected to magnetic resonance imaging (MRI), including use of a diffusion sequence. All patients with pathological enhancement in the scar were then subjected to histological typing. MRI was considered negative in the absence of areas of suspicious enhancement. In all cases it was measured the ADC value in the scar area or in the area with pathological enhancement. The ADC values were compared with MRI findings and histological results obtained.Results: 26 cases were positive/doubtful at MRI and then subjected to histological typing: of these recurrences were 20 and benign were 6. 46 cases were judged negative at MRI and therefore not sent to cyto-histology. The average ADC value of recurrences was statistically lower of scarring (p<0.001).Conclusions: ADC value can be a specific parameter in differential diagnosis between recurrence and scar. The diffusion sequence, in association with the morphological and dynamic sequences, can be considered a promising tool for the surgical indication in suspected recurrence of breast cancer.

Soft tissue discrimination ex vivo by dual energy computed tomography

H. Zachrisson, E. Engström, J. Engvall, L. Wigström, Ö. Smedby, A. Persson — 2010-08-01

Abstract: Purpose: Dual Energy Computed Tomography (DECT) may provide additional information about the chemical composition of tissues compared to examination with a single X-ray energy. The aim of this in vitro study was to test whether combining two energies may significantly improve the detection of soft tissue components commonly present in arterial plaques.Methods: Tissue samples of myocardial and psoas muscle, venous and arterial thrombus as well as fat from different locations were scanned using a SOMATOM Definition Dual Source CT system (Siemens AG, Medical Solutions, Forchheim, Germany) with simultaneous tube voltages of 140 and 80kV. The attenuation (Hounsfield units, HU) at 80 and 140kV was measured in representative regions of interest, and the association between measured HU values and tissue types was tested with logistic regression.Results: The combination of two energy levels (80 and 140kV) significantly improved (p<0.001) the ability to correctly classify venous thrombus vs arterial thrombus, myocardium or psoas; arterial thrombus vs myocardium or psoas; myocardium vs psoas; as well as the differentiation between fat tissue from various locations. Single energy alone was sufficient for distinguishing fat from other tissues.Conclusion: DECT offers significantly improved in vitro differentiation between soft tissues occurring in plaques. If this corresponds to better tissue discrimination in vivo needs to be clarified in future studies.

Endovascular treatment of dural fistulas with the venous outflow of laterocavernous sinus

Xianli Lv, Chuhan Jiang, Youxiang Li, Ming Lv, Zhongxue Wu — 2010-08-01

Abstract: Objective: To report our findings concerning the laterocavernous sinus (LCS) drainage of dural fistulas, focusing our attention on the important implications in treatment of the LCS, which is one of the principal drainage pathways of the superficial middle cerebral vein (SMCV).Methods: Consecutive 32 patients with dural fistulas treated endovascularly between 2005 and 2008 were reviewed. Seven patients had angiographic features such as dural fistulas draining with SMCV via LCS. Clinical records for these 7 patients were focused to determine their presenting symptoms, angiographic features, endovascular treatments, and clinical outcomes.Results: Over 3 years, 7 patients had 7 dural fistulas drained with SMCV via LCS were treated. Six-vessel angiography confirmed the presence of the dural fistulas. All fistulas were Cognard Type III featured by leptomeningeal veins drainage. One fistula involving the lesser sphenoid wing and 6 fistulas involving CS were supplied by external carotid artery branches with or without dural branches of the internal carotid artery. LCS was identified as a contiguous to SMCV drainage in these cases. One patient was treated with transvenous coil embolization alone, two with transvenous a combination of Onyx and coil embolization, and 4 with transarterial embolization. An angiographic obliteration and clinical cure was achieved in all patients. Complication was local hair loss due to X-ray radiation in one patient.Conclusion: It is very important to diagnose the presence of LCS in dural fistulas during the diagnostic angiography. It is believed that the knowledge of LCS might be relevant for the understanding and treatment of dural fistulas involving the LCS.

Paediatric radiology and scientific contributions to radiation dose at the meeting of the German Radiological Society—An analysis of an 11-year period

Christoph M. Heyer, Stefan P. Lemburg, Sören A. Peters — 2010-08-01

Abstract: Aim: Evaluation of the emphasis on themes pertaining to paediatric radiology and radiation dose at the Meeting of the German Radiological Society from 1998 to 2008 in comparison to international data.Materials and methods: Retrospective analysis of 9440 abstracts with documentation of type of contribution, imaging modality, and examined body region. Abstracts primarily dealing with paediatric radiology and those stating radiation dose were documented. Results were compared with a Pubmed query.Results: 448 contributions in paediatric radiology were presented corresponding to 5% of all abstracts with an increase from 5 (1998) to 7% (2008). The proportion of prospective studies of all congress contributions was 10%, whereas in paediatric radiology, the share of prospective studies was 6%. From 1998 to 2008, the share of MRI fell from 48 to 38%, while CT contributions rose from 30 to 34%. Within paediatric radiology, the proportion of CT rose from 23 to 29%, while MRI and ultrasound fell from 63 to 48% and 35 to 19%, respectively. The share of abstracts dealing with radiation dose rose from 7 to 10% while that primarily pertaining to dose reduction grew from 2 to 4%. Of all abstracts concerning CT, 15% touched on radiation dose, whereas 6% primarily dealt with dose reduction. Among all abstracts dealing with paediatric radiology, 20 and 6% mentioned radiation dose and dose reduction, respectively. In the subgroup of paediatric radiology CT abstracts, radiation dose and dose reduction were mentioned in 34 and 16%, respectively. An online query produced 137,791 publications on CT, of whose abstracts 3% mentioned radiation dose and 0.5% mentioned dose reduction. 11% of all CT publications dealt with paediatric populations and 2% of these publications examined questions of radiation dose.Conclusions: In the last 11 years the Meeting of the German Radiological Society has presented a growing number of contributions pertaining to paediatric radiology. CT has shown the most pronounced growth of all contributions. Paediatric radiology has significantly more often dealt with questions of radiation exposure than those from general radiology. However, contributions with definite reference to radiation dose, both pertaining to all publications and specifically to those dealing with CT, remain a minority, albeit with a higher proportion when compared to international data.

Evaluation of left atrial function by multidetector computed tomography before left atrial radiofrequency-catheter ablation: Comparison of a manual and automated 3D volume segmentation method

2010-08-01

Abstract: Introduction: The purpose of this study was to compare a manual and automated 3D volume segmentation tool for evaluation of left atrial (LA) function by 64-slice multidetector-CT (MDCT).Methods and materials: In 33 patients with paroxysmal atrial fibrillation a MDCT scan was performed before radiofrequency-catheter ablation. Atrial function (minimal volume (LAmin), maximal volume (LAmax), stroke volume (SV), ejection fraction (EF)) was evaluated by two readers using a manual and an automatic tool and measurement time was evaluated.Results: Automated LA volume segmentation failed in one patient due to low LA enhancement (103HU). Mean LAmax, LAmin, SV and EF were 127.7ml, 93ml, 34.7ml, 27.1% by the automated, and 122.7ml, 89.9ml, 32.8ml, 26.3% by the manual method with no significant difference (p>0.05) and high Pearsońs correlation coefficients (r=0.94, r=0.94, r=0.82 and r=0.85, p<0.0001), respectively. The automated method was significantly faster (p<0.001). Interobserver variability was low for both methods with Pearson's correlation coefficients between 0.98 and 0.99 (p<0.0001).Conclusions: Evaluation of LA volume and function with 64-slice MDCT is feasible with a very low interobserver variability. The automatic method is as accurate as the manual method but significantly less time consuming permitting a routine use in clinical practice before RF-catheter ablation.

Computer-aided polyp detection on CT colonography: Comparison of three systems in a high-risk human population

2010-08-01

Abstract: Purpose: To compare the detection performances of two commercial and one academic computer-aided diagnosis (CAD) systems for polyp detection on CT colonography (CTC) in a high-risk human population and to assess their detection characteristics.Materials and methods: This retrospective study had institutional review board approval, but informed consent was waived. Sixty-eight patients who were suspected of having colonic polyps and scheduled for colonoscopic polyp removal were included. After CTC was performed using a 64-row MDCT, two commercial (PEV, CAR) and one academic (Hessian matrix-based) CAD systems were applied to each CTC dataset. Colonoscopy using the segmental unblinded technique was performed as a standard of reference. Per-polyp and per-patient sensitivities were calculated and compared for each CAD system. The mean number of false-positives (FPs) and false-negatives (FNs) was computed and the causes of all FPs and FNs were analyzed.Results: A total of 151 polyps in 61 patients were detected (77 polyps <6mm, 48 6–9.9mm, 26≥10mm). Per-polyp sensitivity for PEV, CAR, and Hessian matrix-based CAD were: 71.6%, 78.4%, and 83.8% for polyps ≥6mm, and 88.5%, 96.2%, and 96.2% for polyps ≥10mm. Per-patient sensitivity for polyps ≥6mm was 80.4%, 89.1%, and 93.5%, and 87%, 95.7%, and 95.7% for polyps ≥10mm, respectively. Per-polyp and per-patient sensitivities were not significantly different among the three CAD systems regardless of size threshold. Mean number of FPs was 6.9 for PEV, 7.3 for CAR, and 14 for Hessian matrix-based CAD. The most common cause of FPs were feces, followed by extracolonic findings, prominent folds and ileocecal valve, and rectal tube. The distribution of the causes of FPs was significantly different among the three systems.Conclusion: Sensitivity of the three CAD systems for polyp detection was comparable regardless of the polyp size threshold; however, the number of FPs was higher in the Hessian matrix-based CAD. In addition, the distribution of the causes of FPs was significantly different among the three systems.

Role of color Doppler indices in predicting disease-free survival of breast cancer patients during neoadjuvant chemotherapy

2010-08-01

Abstract: The aim of our study was to evaluate whether blood flow in locally advanced and inflammatory breast cancer before and after neoadjuvant chemotherapy using color Doppler ultrasonography can be used to monitor the response to therapy and identify possible correlations between survival and various Doppler indices. Fifty patients with breast cancer underwent Doppler evaluation of the tumor with determination of Doppler indices such as pulsatility index (PI), resistive index (RI), and peak systolic velocity (PSV). RI and PI decreased in 27 (54%) and 20 (40%) patients, respectively, and increased in 23 (46%) and 30 (60%) patients, respectively. Thirty (60%) patients showed a decrease in PSV and 20 (40%) patients an increase. Patients with an intratumoral blood flow velocity increase after chemotherapy had a greater likelihood of local recurrence and metastasis compared with patients in whom flow velocity decreased after chemotherapy. The study also confirmed a greater correlation between Doppler PSV and clinical assessment. Tumor flow velocity measured by Doppler ultrasound can be used as an independent marker of disease-free survival in patients with breast cancer.

Christian Loewe — 2010-08-01

Cardiac radiology has shown an extraordinary progress during the last several years, leading to a daily increasing number of books published about cardiac radiology. Most of them are of really excellent quality, but sometimes hampered by the fact that most of them are organized mainly depending on imaging modalities. With other words, a lot of books are available dealing with cardiac MRI OR cardiac CT – and other, more “non-radiological” cardiac imaging methods are not included. For people starting with cardiac imaging and people learning, this situation is not ideal, since they have to read more than one book and have to switch between different volumes.

Christian Loewe — 2010-08-01

Due to the exciting technical progress and the fundamental changes in magnetic resonance imaging—especially in the musculoskeletal system—a second edition of the well-established volume was mandatory. Compared to the first edition—published in 2001—the nowadays well-accepted and implemented technique of high-field MR imaging using 3T systems was incorporated in the text. However, the authors still followed their basic principle that “less is more” and avoided to significantly increase the volume of the present second edition.

Zainab Mustapha — 2010-08-01

This book was interesting reading, however turned out to be quite basic and for this reason I believe Medical students will find it very interesting as it will assist them greatly during there clinical posting. I believe young clinicians starting out in the practice of Medicine will find this text useful. The images were of good quality and the CD attached is a good addition. I recommend a more detailed obstetrics and gynaecology chapter in future editions

Zainab Mustapha — 2010-08-01

What an amazing MUST READ BOOK! This is a supersimplification of the commonest CT and MRI differential diagnosis with supplementary specific imaging findings to be expected for each diagnostic entity. However, the author overlooked geographical variation in the surgical sieving of the differential diagnosis.

Calendar of Events

2010-08-01

Short Instructions to Authors

2010-08-01